1. Field of the Invention
The present invention relates to hexahydrotriazine compounds, a process for preparing the same and insecticides containing the same as active ingredients. The hexahydrotriazine compounds provided by this invention are represented by the following general formula (I): ##STR1##
wherein R stands for lower alkyl or lower alkenyl; R.sub.1 stands for hydrogen, lower alkyl, lower alkenyl, lower alkynyl or a group indicated by ##STR2##
and R.sub.2 stands for a group indicated by ##STR3##
2. Prior Art
A variety of chemicals have been developed and used as insecticides for controlling harmful insects. Representative examples of such chemicals are organic phosphorous compounds, carbamate compounds and synthetic pyrethroids. However, by the repeated use of these insecticides, many harmful insects have acquired resistance to these chemicals, thus making it difficult to control such insects. On the other hand, although some conventional insecticides have high insecticidal activity, they might cause environmental pollution problems either due to their high toxicity to warm-blooded animals or fishes and Crustacea or due to their remaining in the environment in large amounts for a long time after use, thus putting the ecological system out of order. Accordingly, there is a demand for the development of novel insecticides which more effectively control harmful insects, which have acquired resistance to conventional chemicals, and yet are low in toxicity not only to warm-blooded animals but also fishes and Crustacea. There is also a demand for novel insecticides which remain in plants and soils in decreased amounts after their use, and do not produce phytotoxicity in various plants.